But it wasn't because it was too expensive a proposition. In fact, Omidyar says he's prepared to spend the $250 million it would've cost to buy the post on the news startup headed by Glenn Greenwald, the blogging journalist best known for his scoops about the National Security Administration's surveillance practices.

A $250 million war chest would make Greenwald's venture one of the best-funded news startups ever. By way of comparison, the Huffington Post had raised $37 million at the time AOL purchased it, for $315 million, in 2011. It had close to 200 employees at the time. Buzzfeed has raised $46 million and has more than 300 employees.

With $250 million, Greenwald can think even bigger. How big? Well, The New York Times, which has about 1,200 journalists on its payroll, has an annual newsroom budget of around $200 million. So not quite that big, assuming it's meant to last more than a year. But certainly bigger than ProPublica, the investigative news nonprofit, which spends $10 million a year.

While the Greenwald/Omidyar venture will clearly be a mission-driven organization, like ProPublica, it won't be a nonprofit. Omidyar is funding it directly, not through his philanthropic Omidyar Network. On a smaller scale, he's already the primary backer of another for-profit news startup, Honolulu Civil Beat.

Through Omidyar Network, he has invested in news-and-information ventures including Global Voices, the Sunlight Foundation and the Transparency and Accountability Initiative.

What ties together all his activities is a belief that democracy can't function right without journalism that gives voters the information they need to make smart decisions, catalyzed by a newer conviction -- which he shares with Greenwald -- that prosecution of whistleblowers is putting that kind of work in jeopardy.